SrCuervo
Idea: Maybe after a few years, before Hero a short time before Hero Party is formed, create a “Singularity” Magic which can only be used by a single person, and if someone, whether it’s a doppelgänger or mimic or even a mimicry golem, as soon as they try to imitate Mc’s magic they blew up, dying instantly. Like the magic series knowledge can only be acquired and used by only one person until the user dies and the new one arises. This can be a great way to deal with those annoyaning copying enemies or backstabbers.